Getting a NoClassDefFoundError: org/apache/hadoop/fs/FSDataInputStream when adding a plugin

I am trying to use my plugin in Druid and when I try to start Druid services, I get this error message:

2020-03-10T15:24:03,385 INFO [main] org.apache.druid.initialization.Initialization - Adding implementation [org.apache.druid.query.MyDruidModule] for class [interface org.apache.druid.initialization.DruidModule] from local file system extension

2020-03-10T15:24:04,819 WARN [main] org.apache.hadoop.util.NativeCodeLoader - Unable to load native-hadoop library for your platform… using builtin-java classes where applicable

Exception in thread “main” java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FSDataInputStream

at java.lang.Class.getDeclaredConstructors0(Native Method)

at java.lang.Class.privateGetDeclaredConstructors(Class.java:2671)

at java.lang.Class.getDeclaredConstructors(Class.java:2020)

at com.google.inject.spi.InjectionPoint.forConstructorOf(InjectionPoint.java:245)

at com.google.inject.internal.ConstructorBindingImpl.create(ConstructorBindingImpl.java:100)

at com.google.inject.internal.InjectorImpl.createUninitializedBinding(InjectorImpl.java:661)

at com.google.inject.internal.UntargettedBindingProcessor$1.visit(UntargettedBindingProcessor.java:51)

at com.google.inject.internal.UntargettedBindingProcessor$1.visit(UntargettedBindingProcessor.java:35)

at com.google.inject.internal.UntargettedBindingImpl.acceptTargetVisitor(UntargettedBindingImpl.java:42)

at com.google.inject.internal.UntargettedBindingProcessor.visit(UntargettedBindingProcessor.java:35)

at com.google.inject.internal.UntargettedBindingProcessor.visit(UntargettedBindingProcessor.java:27)

at com.google.inject.internal.BindingImpl.acceptVisitor(BindingImpl.java:93)

at com.google.inject.internal.AbstractProcessor.process(AbstractProcessor.java:56)

at com.google.inject.internal.InjectorShell$Builder.build(InjectorShell.java:187)

at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:104)

at com.google.inject.Guice.createInjector(Guice.java:99)

at com.google.inject.Guice.createInjector(Guice.java:73)

at com.google.inject.Guice.createInjector(Guice.java:62)

at org.apache.druid.initialization.Initialization.makeInjectorWithModules(Initialization.java:419)

at org.apache.druid.cli.GuiceRunnable.makeInjector(GuiceRunnable.java:68)

at org.apache.druid.cli.ServerRunnable.run(ServerRunnable.java:56)

at org.apache.druid.cli.Main.main(Main.java:118)

Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FSDataInputStream

at java.net.URLClassLoader.findClass(URLClassLoader.java:382)

at java.lang.ClassLoader.loadClass(ClassLoader.java:418)

at java.lang.

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